Housing less transverse flux electrical machine

ABSTRACT

A housingless transverse flux electrical machine (TFEM) includes a pair of halves adapted to receive therein a plurality of cores and a coil therein. The halves are the exterior boundary for the environment and the TFEM can be in operating configuration without further housing.

CROSS-REFERENCES

The present invention relates to, claims priority from and is anon-provisional patent application of U.S. Provisional PatentApplication No. 61/704,793, filed Sep. 24, 2012, entitled MODULARTRANSVERSE FLUX ELECTRICAL MACHINE, these documents are incorporatedherein by reference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to transverse flux electrical machines.The present invention more specifically relates to transverse fluxalternators and motors assembly.

2. Description of the Related Art

Alternators and motors are used in a variety of machines and apparatusesto produce electricity from mechanical movements. They find applicationsfor energy production and transportation, to name a few. Alternators andmotors can use Transverse Flux Permanent Magnet (TFPM) technologies.

Transverse flux machines with permanent magnet excitation are known fromthe literature, such as the dissertation by Michael Bork, Entwicklungund Optimierung einer fertigungsgerechten Transversalfluβmaschine[Developing and Optimizing a Transverse Flux Machine to Meet ProductionRequirements], Dissertation 82, RWTH Aachen, Shaker Verlag Aachen,Germany, 1997, pages 8 ff. The circularly wound stator winding issurrounded by U-shaped soft iron cores (yokes), which are disposed inthe direction of rotation at the spacing of twice the pole pitch. Theopen ends of these U-shaped cores are aimed at an air gap between thestator and rotor and form the poles of the stator. Facing them,permanent magnets and concentrators are disposed in such a way that themagnets and concentrators that face the poles of a stator core have theopposite polarity. To short-circuit the permanent magnets, which in therotor rotation are intermittently located between the poles of thestator and have no ferromagnetic short circuit, short-circuit elementsare disposed in the stator.

Put otherwise, transverse flux electrical machines include a circularstator and a circular rotor, which are separated by an air space calledair gap, that allows a free rotation of the rotor with respect to thestator, and wherein the stator comprises soft iron cores, that directthe magnetic flux in a direction that is mainly perpendicular to thedirection of rotation of the rotor. The stator of transverse fluxelectrical machines also comprises electrical conductors, defining atoroid coil, which is coiled in a direction that is parallel to thedirection of rotation of the machine. In this type of machine, the rotorcomprises a plurality of identical permanent magnet parts, which aredisposed so as to create an alternated magnetic flux in the direction ofthe air gap. This magnetic flux goes through the air gap with a radialorientation and penetrates the soft iron cores of the stator, whichdirects this magnetic flux around the electrical conductors.

In the transverse flux electrical machine of the type comprising arotor, which is made of a plurality of identical permanent magnet parts,and of magnetic flux concentrators, the permanent magnets are orientedin such a manner that their magnetization direction is parallel to thedirection of rotation of the rotor. Magnetic flux concentrators areinserted between the permanent magnets and redirect the magnetic fluxproduced by the permanent magnets, radially towards the air gap.

The transverse flux electrical machine includes a stator, whichcomprises horseshoe shaped soft iron cores, which are oriented in such amanner that the magnetic flux that circulates inside these cores, isdirected in a direction that is mainly perpendicular to the axis ofrotation of the rotor.

The perpendicular orientation of the magnetic flux in the cores of thestator, with respect to the rotation direction, gives to transverse fluxelectrical machines a high ratio of mechanical torque per weight unit ofthe electrical machine.

It is therefore desirable to produce an electrical machine that is easyto assemble. It is also desirable to provide an electrical machine thatis economical to produce. Other deficiencies will become apparent to oneskilled in the art to which the invention pertains in view of thefollowing summary and detailed description with its appended figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a TFEM in accordance with at least oneembodiment of the invention;

FIG. 2 is an isometric view of a TFEM in accordance with at least oneembodiment of the invention;

FIG. 3 is a right side elevational view of a TFEM in accordance with atleast one embodiment of the invention;

FIG. 4 is a left side elevational view of a TFEM in accordance with atleast one embodiment of the invention;

FIG. 5 is a top plan view of a TFEM in accordance with at least oneembodiment of the invention;

FIG. 6 is a bottom plan view of a TFEM in accordance with at least oneembodiment of the invention;

FIG. 7 is a rear elevational view of a TFEM in accordance with at leastone embodiment of the invention;

FIG. 8 is a front elevational view of a TFEM in accordance with at leastone embodiment of the invention;

FIG. 9 is an isometric semi-exploded view of a TFEM illustrating astator portion and a rotor portion in accordance with at least oneembodiment of the invention;

FIG. 10 is an isometric semi-exploded view of a portion of a TFEMillustrating a rotor portion in accordance with at least one embodimentof the invention;

FIG. 11 is an isometric semi-exploded view of a TFEM illustratingmultiple phase modules of a stator portion in accordance with at leastone embodiment of the invention;

FIG. 12 is a magnified section of an isometric semi-exploded view of aTFEM in accordance with at least one embodiment of the invention;

FIG. 13 is a section view of a TFEM illustrating multiple phase modulesin accordance with at least one embodiment of the invention;

FIG. 14 is a section view of a TFEM illustrating cores pairs in a statorportion in accordance with at least one embodiment of the invention;

FIG. 15 an isometric view of a core in accordance with at least oneembodiment of the invention;

FIG. 16 an isometric semi-exploded view of a phase module of a statorportion in accordance with at least one embodiment of the invention;

FIG. 17 an isometric semi-exploded view of a phase module of a statorportion in accordance with at least one embodiment of the invention;

FIG. 18 an isometric partial assembly of a phase module in accordancewith at least one embodiment of the invention;

FIG. 19 an isometric partial assembly of cores with a coil in accordancewith at least one embodiment of the invention;

FIG. 20 a front elevational view of a phase module illustrating relativeangles thereof in accordance with at least one embodiment of theinvention;

FIG. 21 a front elevational view of a phase module illustrating relativeangles thereof in accordance with at least one embodiment of theinvention;

FIG. 22 is an isometric view of a portion of a coil and cores assemblyin accordance with at least one embodiment of the invention;

FIG. 23 is isometric view of a portion of a phase module assembly inaccordance with at least one embodiment of the invention;

FIG. 24 is isometric view of a portion of a phase module assembly inaccordance with at least one embodiment of the invention;

FIG. 25 is a section view of a core module in accordance with at leastone embodiment of the invention;

FIG. 26 is a section view of a coil in accordance with at least oneembodiment of the invention;

FIG. 27 is an isometric view of a phase module assembly in accordancewith at least one embodiment of the invention;

FIG. 28 is an isometric view of a phase module assembly in accordancewith at least one embodiment of the invention;

FIG. 29 is an isometric view of a phase module assembly in accordancewith at least one embodiment of the invention;

FIG. 30 is an isometric view of a phase module assembly in accordancewith at least one embodiment of the invention;

FIG. 31 is an isometric view of a phase module assembly in accordancewith at least one embodiment of the invention;

FIG. 32 is an isometric view of a phase module and jig assembly inaccordance with at least one embodiment of the invention;

FIG. 33 is an isometric view of a phase module and jig assembly readyfor resin injection in accordance with at least one embodiment of theinvention;

FIG. 34 is a side elevational view of a resin-injected stator modulebefore being machined and/or honed in accordance with at least oneembodiment of the invention;

FIG. 35 is flow chart representative of assembly steps in accordancewith at least one embodiment of the invention; and

FIG. 36 is flow chart representative of resin injection steps inaccordance with at least one embodiment of the invention.

SUMMARY OF THE INVENTION

It is one aspect of the present invention to alleviate one or more ofthe shortcomings of background art by addressing one or more of theexisting needs in the art.

The following presents a simplified summary of the invention in order toprovide a basic understanding of some aspects of the invention. Thissummary is not an extensive overview of the invention. It is notintended to identify key/critical elements of the invention or todelineate the scope of the invention. Its sole purpose is to presentsome concepts of the invention in a simplified form as a prelude to themore detailed description that is presented later.

Generally, an object of the present invention provides a modularTransverse Flux Electrical Machine (TFEM), which can also be morespecifically appreciated as Transverse Flux Permanent Magnet (TFPM),which includes phase modules thereof.

An object of the invention is generally described as a modularelectrical machine including a plurality of phase modules adapted to beaxially assembled.

Generally, an object of the invention provides a TFEM including aplurality of phase modules assembled together with an intervening phaseshift generally set at 120° [electrical] to provide standard symmetricalelectric current overlapping over a complete 360° electrical cycle. Atwo-phases electrical machine would have a 90° phase shift and would usea similar logic and is also encompassed by the present invention.

One object of the invention provides at least one phase module includingcooperating halves.

At least one object of the invention provides at least one phase moduleincluding a plurality of cores, and associated poles, angularly spacesapart from one another with different angular distances therebetween.

At least one aspect of the invention provides at least one phaseincluding at least three adjacent cores, and associated poles, angularlydistanced apart with a substantially similar angular distancetherebetween and each at least three adjacent cores being furtherangularly spaced apart from an adjacent at least three adjacent cores,and associated poles, with a different angular distance thereof.

At least one aspect of the invention provides at least two adjacentcores, and associated poles, angularly radially separated with an angleof 10.8° and angularly radially separated from adjacent cores with atleast one significantly different angle.

At least one object of the invention provides a set of poles, andintervening angular distance therebetween, that is repeated at least twotimes in a phase to locate the poles in the phase module.

At least one object of the invention provides a modular TFEM including aplurality of phase modules axially secured together by opposed supportportions.

At least one aspect of the invention provides a phase module including aplurality of identical angular portions thereof.

At least one aspect of the invention provides a plurality of angularportions having intervening locating mechanism thereof adapted to locateand secure adjacent angular portions together.

At least one aspect of the invention provides an angular portionincluding a wire opening thereof adapted to receive therein coil wiresextending outside the phase module.

At least one object of the invention provides a TFEM including a statorskewing angularly locating cores therein in respect with the rotationaxis of the TFEM.

At least one object of the invention provides a plurality of phasemodules including a cooperating positioning mechanism thereof adapted tomechanically angularly locate adjacent phase modules axially assembledtogether.

At least one aspect of the invention provides at least one phase moduleincluding a plurality of core-receiving spaces thereof.

At least one aspect of the invention provides at least one phase moduleincluding a housing including a circumferential cavity adapted toreceive therein a cooperating portion of the cores to furthermechanically radially locate and secure the cores to the phase modulehousing.

At least one object of the invention provides a phase modules includinga plurality of angular portions adapted to be sequentially assembledtogether to allow inserting a coil therein before all the angularportions are assembled together.

At least one object of the invention provides a phase module including aplurality of angular portions configured to allow insertion of a coiltherein when the assembled angular portions are angularly covering lessthan 200°.

At least one object of the invention provides a TFEM stator includingresin therein for securing the coil and the cores inside the angularportions and also to maintain them in their respective locations whenthe internal portion of the phase module is machined, bored or honed.

At least one object of the invention provides a TFEM stator includinginjected resin therein for securing the angular portions together withthe coil.

At least one object of the invention provides a housingless rotatabletransverse flux electrical machine (TFEM) comprising a stator includingat least one phase module comprising a pair of opposed halve membersrespectively including a plurality of core-receiving spaces sized anddesigned to receive, locate and secure therebetween a plurality ofcores; and a coil operatively disposed in respect with the cores insideeach phase modules, the pair of opposed halves being the exteriorhousing of the stator allowing the TFEM to be used without furtherhousing.

At least one object of the invention provides a housingless statoradapted to be used in a rotatable transverse flux electrical machine(TFEM), the housingless stator comprising at least one phase modulecomprising a pair of opposed halve members respectively including aplurality of core-receiving spaces sized and designed to receive, locateand secure therebetween a plurality of cores; and a coil operativelydisposed in respect with the cores inside each phase modules, the pairof opposed halves being the exterior housing of the stator allowing theTFEM to be used without further housing.

At least one object of the invention provides a kit for assembling aphase in a rotatable transverse flux electrical machine (TFEM), the kitcomprising a pair of halves; a plurality of cores adapted to be locatedbetween the halves; a coil adapted to be located between the halves inoperating position in respect with the plurality of cores; and resin tosecure the coil and the plurality of cores with the pair of halves.

Embodiments of the present invention each have at least one of theabove-mentioned objects and/or aspects, but do not necessarily have allof them. It should be understood that some aspects of the presentinvention that have resulted from attempting to attain theabove-mentioned objects may not satisfy these objects and/or may satisfyother objects not specifically recited herein.

Additional and/or alternative features, aspects, and advantages ofembodiments of the present invention will become apparent from thefollowing description, the accompanying drawings, and the appendedclaims.

DESCRIPTION OF EMBODIMENT(S) OF THE INVENTION

Our work is now described with reference to the Figures. In thefollowing description, for purposes of explanation, numerous specificdetails are set forth in order to provide a thorough understanding ofthe present invention by way of embodiment(s). It may be evident,however, that the present invention may be practiced without thesespecific details. In other instances, when applicable, well-knownstructures and devices are shown in block diagram form in order tofacilitate describing the present invention.

The embodiments illustrated below depict a TFEM 10 with thirty-two (32)pairs of poles and a 510 mm diameter at the air gap and a 100 mm lengthof the magnets. The configuration of the TFEM 10, an external rotorinstead of an internal rotor, the number of phases can change inaccordance with the desired power output, torque and rotational speedwithout departing from the scope of the present invention.

A TFEM 10 is illustrated in FIG. 1 through FIG. 8. The TFEM 10 includesa stator portion 14 and a rotor portion 18. The stator portion 14 isadapted to remain fixed while the rotor portion 18 is located within thestator portion 14 and is adapted to rotate in respect with the statorportion 14 about rotation axis 22. The TFEM of the illustratedembodiments has a modular construction. Two axial side members 26 aresecured together to assemble three electrical phases 30 together, eachbeing provided by a phase module 32. Each phase module 32 is adapted toindividually provide an electrical phase 30 of alternating current. Thepresent embodiment illustrates three phases 30 axially coupled togetherto provide tri-phased current when the TFEM 10 is rotatably actuated.The pair of axial side members 26 interconnects and axially securestogether the three phases 30. Proper tension is applied to each of theplurality of axial securing members 34 to ensure the phase modules 32remain fixedly secured together. In the present embodiment, each axialside member 26 is provided with a series of extending axial securingmember receiving portions 38 adapted to receive the axial securingmembers 34 therein while the axial securing members 34 extends axiallyoutside the phase modules 32. The axial securing members 34 couldalternatively pass through the phase modules 32, provided with axialopenings therein, in another unillustrated embodiment.

Still referring to FIG. 1 through FIG. 8, the axial side members 26 canbe made of steel or other suitable material providing sufficientmechanical strength for the required purpose. Each axial side members 26is optionally provided with a lifting link 42 sized and designed toreceive therein, for example, a crane hook (not illustrated) to lift andmove the TFEM 10. The axial side members 26 are further equipped with asupport portion 46 adapted to secured thereto a pair of feet 50configured to interconnect both axial side members 26 together and tofurther facilitate securing the TFEM 10 to a base chassis (notillustrated). For instance, the base chassis can be a nacelle when theTFEM 10 is installed in a windmill or alternatively any other chassisprovided by the equipment the TFEM 10 is operatively connected to.

Each axial side member 26 is configured to receive and secure thereto anaxial rotor support member 54. The axial rotor support member 54 isrecessed in a circular cavity 56 (visible in FIG. 9) defined in itsassociated axial side member 26 to concentrically locate the rotorportion 18 in respect with the stator portion 14. The axial rotorsupport member 54 is further removably secured to its associated axialside member 26 with a plurality of fasteners 58. The actualconfiguration of the embodiment illustrated in FIG. 9 allows removal ofthe rotor portion 18 in one axial direction 60 when both axial rotorsupport members 54 are unsecured from their respective axial side member26 because the circular cavities 56 are both located on the same side oftheir respective axial side member 26. This allows for easy maintenanceof the TFEM 10 once installed in its operating configuration with itsexternal mechanism.

As it is also possible to appreciate from the embodiment illustrated inFIGS. 1 through 8, the rotor portion 18 extends through the axial rotorsupport members 54 and rotatably engages both axial rotor support member54. A solid rotor drive member 62 further extends from one axial rotorsupport members 54. The solid drive member 62 could alternatively be ahollowed drive member in another unillustrated embodiment. The drivemember 62 is adapted to transmit rotatable motive power from an externalmechanism (not illustrated) to the TFEM 10 and includes a drive securingmechanism 66 adapted to rotatably couple the drive member 62 of the TFEM10 to a corresponding rotatable drive element from the externalmechanism (not illustrated). The external mechanism (not illustrated)could, for example, be a windmill rotatable hub (not illustrated) towhich the rotor blades (not illustrated) are secured to transmitrotational motive power to the TFEM 10. The external mechanism expressedabove is a non-imitative example and other external mechanisms adaptedto transmit rotational motive power to the TFEM 10 are considered toremain within the scope of the present application.

The TFEM 10 is further equipped with a protective plate 70 adapted tostore and protect electrical connectors and electrical wires thatextends from the TFEM 10 through an electrical outlet 74.

Turning now to FIG. 9 illustrating a semi-exploded TFEM 10 where askilled reader can appreciate the depicted rotor portion 18 is axiallyextracted 60 from the stator portion 14. The rotor portion 18 is axiallyextracted 60 from the stator portion 14 by removing the plurality offasteners 58 and unsecuring the axial rotor support members 54 fromtheir respective associated axial side member 26. It can be appreciatedthat the rotor portion 18 of the exemplary embodiment has three distinctmodular phases 36, each providing an electrical phase 30, adapted toaxially align and operatively cooperate with the three phase modules 32of the exemplified stator portion 14. The rotor portion 18 includes aplurality of magnets 94 and concentrators 98 that are disposed parallelwith the rotation axis 22. An alternate unillustrated embodiment usesskewed magnets 94 and concentrators 98 that are disposed non-parallel(at an angle) with the rotation axis 22.

FIG. 10 illustrates a further exploded view of the rotor portion 18. Asindicated above, the rotor portion 18 is adapted to rotate in respectwith the stator portion 14. The speed of rotation can differ dependingof the intended purpose. Power remains function of the torque and therotation speed of the rotor portion 18 therefore the TFEM is going toproduce more power if the TFEM rotates rapidly as long as its operatingtemperature remains in the operating range of its different parts toprevent any deterioration (e.g. magnet demagnetization or insulatingvanish deterioration, to name a few). The axial rotor support members 54are adapted to be unsecured from the bearing holder 78 by removing theplurality of fasteners 82. A sequence of assembled seal 86, bearing 90and bearing holder 78 is used on the front side of the rotor portion 18while the same type of assembly is used on the opposite axial side ofthe rotor portion 18 to rotatably secure the rotor 80 to the axial rotorsupport members 54. FIG. 10 also illustrates that each phase module 36of the rotor 80 uses a sequence of alternating permanent magnets 94 andconcentrators 98. Strong permanent magnets 94 can be made of Nb—Fe—B asoffered by Hitachi Metals Ltd and NEOMAX Co. Ltd. Alternatively,suitable magnets can be obtained by Magnequench Inc. and part of thistechnology can be appreciated in U.S. Pat. No. 5,411,608, U.S. Pat. No.5,645,651, U.S. Pat. No. 6,183,572, U.S. Pat. No. 6,478,890, U.S. Pat.No. 6,979,409 and U.S. Pat. No. 7,144,463.

A semi-exploded stator portion 14 is illustrated in FIG. 11. The axialside members 26 are exploded from the illustrative three (3) phasemodules 32. Each phase module 32 is going to be discussed in moredetails below. However, a positioning mechanism 102 is provided topolarly locate each phase module 32 in respect with its adjacent phasemodule 32 so that proper phase shift is maintained. Generally, the phaseshift is set at 120° electrical to provide standard symmetrical electriccurrent overlapping over a complete 360° electrical cycle. The 120°phase shift allows to, in theory, eliminate harmonics that are notmultiples of three (3). The 120° phase shift illustrated herein is apreferred embodiment and is not intended to limit the angular phaseshift of the present invention.

The illustrative embodiment of FIG. 11 includes three (3) phase modules32. Another possible embodiment includes a multiple of three (3) phasesmodules 32 mechanically secured together, like the three (3) phasemodules of FIG. 11, and electrically connected by phase 30 to increasethe capacity of the TFEM 10 by simply increasing the axial length of theTFEM 10. Thus, a nine (9) phase modules 32 would be coupledthree-by-three for a three-phased 30 TFEM 10. Another embodiment is aone-phase 30 TFEM 10 including only one phase module 32. One otherembodiment could be a two-phased 30 TFEM 10 electrically coupledtogether in a one-phase 30 configuration and with a phase shift of 90°in a two-phase 30 configuration.

As best seen from FIG. 12, each positioning mechanism 102 is embodied asa protruding portion 106 and corresponding cavity 110 sized and designedto mate together to polarly locate two adjacent phase modules 32together. Additionally, each phase module 32 further includes a circularridge 114 on one axial side and corresponding circular groove 118 on theopposite axis side. Engagement of the circular ridge 114 and circulargroove 118 ensures concentric positioning of adjacent phase modules 32along the rotation axis 22 of the TFEM 10. Other shapes, designs and/ormechanical elements suitable to locate the phase modules 32 and theaxial side members 26 together could be used without departing from thescope of the present application. Additionally, the recessed portion 104is further defined in the phase modules 32 and the axial side members 26to facilitate separation of adjacent assembled phase modules 30 andcooperating axial side members 26 by inserting a tool therein and pryingto separate the two adjacent phase modules 32.

A section view of the TFEM 10 is illustrated in FIG. 13. The rotorportion 18 includes a cylindrical frame 122 preferably removably securedto the rotatable drive member 62 with a series of fasteners 128 via twoplates 124 radially extending from the drive member 62. As explainedabove, the cylindrical frame 122 is sized and designed to accommodatethree electrical phases 30, each provided by a phase module 36 includingits alternate series of magnets 94 and concentrators 98 secured thereon.The circular stator portion 14 and the circular rotor portion 18 areseparated by an air space called “air gap” 126 that allows aninterference-free rotation of the rotor portion 18 with respect to thestator portion 14. Generally, the smallest is the air gap 126 the mostperformance the TFEM is going to provide. The air gap 126 is howeverlimited to avoid any mechanical interference between the stator portion14 and the rotor portion 18 and is also going to be influenced bymanufacturing and assembly tolerances in addition to thermic expansionof the parts when the TFEM 10 is actuated. The stator portion 14comprises soft iron cores (cores) 130 that direct the magnetic flux in adirection that is mainly perpendicular to the direction of rotation ofthe rotor portion 18. The stator portion 14 of TFEM 10 also comprises ineach phase module 32 electrical conductors defining a toroid coil 134that is coiled in a direction that is parallel to the direction ofrotation of the TFEM 10. In this embodiment, the rotor portion 18comprises a plurality of identical permanent magnets 94, which aredisposed so as to create an alternated magnetic flux in the direction ofthe air gap 126. This magnetic flux goes through the air gap 126 with aradial orientation and penetrates the soft iron cores 130 of the statorportion 14, which directs this magnetic flux around the toroid coil 134.

In the TFEM 10 of the type comprising a rotor portion 18 including aplurality of identical permanent magnets 94 and of magnetic fluxconcentrators 98, the permanent magnets 94 are oriented in such a mannerthat their magnetization direction is parallel to the direction ofrotation of the rotor portion 18, along rotation axis 22. Magnetic fluxconcentrators 98 are disposed between the permanent magnets 94 andredirect the magnetic flux produced by the permanent magnets 94 radiallytowards the air gap 126. In contrast, the stator portion 14 comprises“horseshoe-shaped” soft iron cores 130, which are oriented in such amanner that the magnetic flux that circulates inside these cores 130 isdirected in a direction that is mainly perpendicular to the direction ofrotation of the rotor portion 18. The perpendicular orientation of themagnetic flux in the cores 130 of the stator portion 14, with respect tothe rotation direction, gives to TFEM a high ratio of mechanical torqueper weight unit of the electrical machine.

The rotor portion 18 has been removed in FIG. 14 illustrating anencumbrance-free section view of the stator portion 14. One canappreciate a plurality of pole faces 138 extending from each core's 130legs 142 (as best seen in FIG. 15). The pole faces 138 are disposed atan angle α from the rotation axis 22 of the TFEM 10. The angle α of thepole faces 138 is called stator skew and is one of a plurality ofelements that can be acted upon to reduce or cancel the ripple torqueand the cogging torque. The stator skew allows for progressiveelectromagnetic interaction between the cores 130 and the magnets 94 andthe concentrators 98.

Focusing on the stator skew element, in reference with FIG. 14 throughFIG. 18, a plurality of cores 130 are disposed in each phase module 32of the stator portion 14. Yet another element to consider is the numberof pairs of poles n. The number of pairs of poles n is equal to thenumber of cores 130 given that there are two poles 138 per core 130. Thenumber of magnets 94 is equal to the number of concentrators 98 andtheir number is twice the number of pairs of poles n and consequentlyalso twice the number of cores 130. The number of pairs of poles n ispreferably thirty-two (32) as exemplified in the present application.

Therefore, each core 130 includes a pair of poles 144 extending fromrespective core's legs 142 (not visible in FIG. 14 but illustrated inFIG. 15). Each core 130 ends with two poles 136 having respective polefaces 138 thereof that can be seen inside the stator module 14illustrated in FIG. 14. Each pole 136 of a pair of poles 144 is offset132 to locate each pole 136 from a pair of poles 144 at a distancethereof that is generally equivalent to a distance of two adjacentconcentrators 98 on the rotor portion 18 (commonly referred to as “polepitch”). The core 130 of the illustrated embodiment includes a pair ofopposed locating portions 148 adapted to locate the core 130 in thephase module 32. The locating portions 148 are embodied in theillustrative core 130 in FIG. 15 as protrusions 160 extending from theopposed sides of the core 130. The skewed pole faces 138 of anembodiment are a projection toward the rotation axis 22 of the angledcore's legs 142. Each pair of pole faces 138 can be skewed, or angled,to more or less progressively engage the electromagnetism of the magnets94 and the concentrators 98 on the rotor portion 18, on the other sideof the air gap 126, when the rotor portion 18 is operatively assembledwith the stator portion 14. The angle α of the pole faces 138 of theillustrated embodiment is provided by the angle of the core's legs 142that is dictated by the design and the shape of the core-receivingspaces 140 in the phase module 32 assembly as illustratively embodied inFIG. 16 and FIG. 17.

In the present embodiment, as shown in FIG. 16, each stator phase module33 is built with a sufficiently mechanically resistant material machinedto form proper shapes therein and includes four angular portions 146(for instance, four angular portions 146 of 90° [mechanical] each=360°[mechanical] once assembled together for a complete stator phase module32) that are assembled together to locate and secure the cores 130 andthe coil 134 within the phase module 32. The embodiment illustrated inFIG. 16 uses four (4) angular portions 146 and could alternatively use adifferent number of angular portions 146 as long as they complete 360°[mechanical] without departing from the scope of the presentapplication; an embodiment including a modular phase 32 with two angularportions 146 is illustrated in FIG. 17. A three angular portions 146embodiment is also contemplated and within the scope of the presentinvention. The angular portion 146 illustrated in FIG. 18 includes twohalves 150 secured together with fasteners 154 and further respectivelylocated with pins 158. The halves 150 are sized and designed to receivetherein a predetermined number of cores 130 with a precise stator skewangle α (identified in FIG. 19, inter alia). One can appreciate that thedistances between the angular sides of the angular portion 146 and theirfirst respective adjacent core 130 is not the same on each halve 150because of the core 130 skewing. This could have an influence onreference locations of the angles indicated in FIG. 20 and FIG. 21depending of the reference point used to locate the cores 130.

The phase module 30 can alternatively be constructed with an alternatedhalves 150 disposition to prevent having halves 150 evenly angularlydisposed on each side of the phase module 30. The alternate layout ofthe halves 150 over the circumference of a complete phase module 30 thusincreases the mechanical strength of the phase module 30 because thejunction between two adjacent angular portions 146 (on one side of thephase module 30) is going to be mirrored (on the opposite side of thephase module 30) by a continuous portion of the counterpart opposedhalve 150. In this embodiment, the fact that the halves 150 are notangularly evenly disposed along the circumference of a phase module 30on each side thereof, implies that the angular portions 146 areoverlapping each other.

FIG. 19 depicts some isolated cores 130 and associated coil 134sub-assemblies to more clearly illustrate the angle α of the statorskew. The cores 130 and the coil 134 are in the same relative positionas if they were within their angular portion 146 (not illustrated), bothhalves 150 (not illustrated) of the angular portion 146 however, hasbeen removed so that a reader can better appreciate the relativeposition of the cores 130 and the coil 134 in the assembly. From FIG.19, the skilled reader can appreciate that the cores 130 arecollectively disposed precisely at angle α to provide the desired statorskew and also respectively disposed at predetermined angular distancesfrom each other.

Moving now to FIG. 20 and FIG. 21, a skilled reader can appreciate theangles about which are respectively polarly located the cores 130 in aphase module 32. The angles are applied to four (4) angular portions 146of the embodiment (as indicated above, the illustrated embodiment hasfour (4) angular portions of 90° each). The relative angles are to beconsidered between a same reference point on each core 130. Morespecifically, FIG. 20 depicts an angular portion 146 including eight (8)cores 130 respectively identified C1-C8. In this embodiment, cores C1-C4form a set 148 of poles 136 where the intervening angles (10.781°[mechanical]) between the repeated angular sequences of poles A, B, C, Dis constant. The intervening angle (10.781° [mechanical]) could bedifferent and remain constant if the number of cores 130 present in aset 148 of poles 136 is different without departing from the scope ofthe present application.

A set 148 of poles 136 is repeated with intervening radial angle 152that has a value adapted to complete an angle of 45° [mechanical] 156 inthe present illustrative embodiment. The actual intervening angle 152 ofthe illustrated embodiment is 12.656° [mechanical] and this angle,required to complete the angle of 45° of the embodiment, could bedifferent should another configuration of set 148 of poles 136 bedesirable. In other words, a new set of poles 148 begins each 45°[mechanical] and is repeated a number of times in the presentconfiguration. The number of sets 148 in the illustrative embodiment iseight (8), two per angular portion 146 of 90°. The angle of 45° of theembodiment is 360° [mechanical]/8 and could alternatively be 30°, 60° or90° and fit in the angular portion 146 of 90° in the illustratedembodiment.

Another unillustrated embodiment of sets 148 includes two (2) cores 130with a predetermined intervening angular distance (or angle thereof).The set 148 of two cores 130 is separated from the next set 148 of twocores 130 with a different intervening angular distance. This alternaterepetitive arrangement of sets 148 is used to build a complete phasemodule 32. One can appreciate from the illustrated embodiment that thecores 130 are identical and their respective locations dictate therespective locations of their associated poles 136. Other possibleembodiment could use cores 130 that are not all identical and thelocation the poles 136 in the stator module 14 should prevail to ensureproper function of the TFEM.

In reference now with FIG. 22 is illustrated an angled portion 146subassembly where a plurality of cores 130 are inserted in theirrespective core-receiving space 140 defined in one halve 150. Eachcore-receiving space 140 is machined or shaped in the halve 150 at aprecise angular position to properly locate each core 130 thereof. Thecore-receiving space 140 extends to a circumferential cavity 164 sizedand designed to receive therein the locating portion 148 of each core130. The circumferential cavity 164 is axially deeper than the depth ofthe core-receiving space 140 to define an edge adapted to abut thelocating portion 148, and appended edge 166, and therefore radiallylocates the core 130 in the phase module 32. The circumferential cavity164 can be continuous around each halves 150 or be discontinuous asillustrated in FIG. 22 and FIG. 23. A discontinuous circumferentialcavity 164 allows for less material removal and increased mechanicalstrength of the phase module 32. A protrusion 168 is radially proximallylocated between core-receiving spaces 140 to further support the cores130 and to create a proximal wall portion when two cooperating halves150 are assembled together to form an angular portion as it isillustrated in FIG. 24. Similarly, a radial edge 192, circumventlydefined in a distal wall portion 196, further axially locates the twoassembled halves 150 and creates an external wall of the phase module32. Thus, two assembled halves 150 create a solid housing surroundingself-localized cores 130 secured therein. Each halve 150 is furtherprovided with internal pillar members 172 adapted to mirror withcorresponding internal pillar members 172 of the other cooperating halve150 and prevent, inter alia, deformation of the halves 150 when they aresecured together with fasteners through openings 176 disposed in some ofthe pillar members 172. A skilled reader can understand that thecore-receiving spaces 140 of two cooperating halves 150 are notmirroring each other because they are intended to receive therein cores130 that have poles offset 132 and also because of the angle α of thestator skew, as described above.

Still referring to FIG. 22, FIG. 23 and FIG. 24, each halve 150 includesa unification mechanism 180 adapted to unite and locate two adjacentangular portions 146. The unification mechanism 180 illustrated in theembodiments includes a male portion 184 and a corresponding femaleportion 188. The male portion 184 is sized and designed to match thefemale portion 188 and ensures proper mechanical connection between theangular portions 146.

FIG. 25 depicts a section view of a phase module 32 with two assembledhalves 150. It is possible to appreciate the position of the core 130enclosed in the phase module 32, however, the circular phase module 32and the skewed core 130 render a little non-obvious the interpretationof FIG. 25.

FIG. 26 represents a section view of an isolated coil 134 including aplurality of conductive wire 200 windings covered with a layer ofinsulating resin 204. It can be noted the illustrated embodimentincludes a plurality of conductive wire 200 windings although otherunillustrated embodiments can use a single or multiple conductive wiresto form the coil 134. The conductive wire 200 illustrated in theembodiment has a rectangular, or oblong, section to maximize theconductive wire 200 density in the coil 134 (less empty space). Anadditional insulating layer 208, made of fabric in the embodiedillustration, is added over the coil 134 to protect the conductive wires200 and the insulating resin 204 to be damaged by mechanical contactswith the halves 150 during installation.

Moving now to the angular portions 146 assembly illustrated in FIG. 27through FIG. 31. A first assembled angular portion 146 is secured to afirst jig plate 212. The angular portion 146 is located with locatingrings 224 disposed on the jig plate 212 to mechanically position theangular portions 146 thereof. The coil 134 is introduced between thelegs 142 of the cores 130 disposed in the angular portion 146 once thefirst angular portion 146 is installed on the first jig plate 212. Thefirst angular portion 146 to be installed on the jig plate 212 ispreferably the angular portion 146 including a wire opening 216 adaptedto pass through the connecting wires 220 extending from the coil 134. Itmight be more difficult to assemble the angular portions 146 if one doesnot begin the assembly with the angular portion 146 including the wireopening 216. A second angular portion 146 is assembled as illustrated inFIG. 28 and FIG. 29 adjacent to the angular portion 146 alreadyinstalled on the jig plate 212. A third and a fourth angular portions146 are simultaneously assembled to complete the angular portions 146assembly as it can be appreciated in FIG. 30. The final angular portion146 assembly is preferably made with a 180° angular portion 146sub-assembly to ensure the male portions 184 and the female portions 188of the angular portions 146 are easily engaging. FIG. 31 illustratesfour (4) angular portions 146 assembled together and supported by thejig plate 212 in accordance with an illustrative embodiment of theinvention. Another possible unillustrated embodiment encompassed by thepresent invention includes only two halves 150 to build a phase module32, one on each side of a phase module 32, each halve 150 radiallycovering 360° of the phase module 32, about the rotation axis 22, toenclose the cores 130 and the coil 134 therein.

A second jig plate 214 is added to the assembled angled portions 146 tosecure the phase module 32 between the two jig plates 214 as illustratedin FIG. 32. A series of fasteners are engaged through the jig plates 212and angled portions 146 assembly and secured to the jig plates 212, 214and the phase module 32 together in a tight manner—a seal can beused—preventing leakage between the jig plates 212 and the phase module32. The second jig plate portion 214 includes a central wall portion 218sized and designed to seal the central portion 232 of the phase module32 between the two jig plates 212—here again a seal can be used. Theassembled jig portions 212, 214 and the sealed intervening phase module32 hence becomes an injection mold in which is injected a resin, or apolymer, adapted to cure and secure all the cores 130 and the coil 134in the halves 150 of the phase module 32.

Resin or polymer is used to interconnect the parts contained in eachphase module 32. Each phase module 32 is injected separately in theillustrative embodiment however one skilled in the art could understandit is possible to collectively inject all the assembled phase module 32together with a properly designed assembly process and a jig sized anddesigned accordingly. The resin 248, preferably, has to meet two maincriteria: 1) sufficient mechanical strength, 2) sufficient thermicconductivity and 3) electrical resistivity. These three requirementsensure all parts of a phase module 32 are adequately maintained togetherat their respective locations. The injected resin 248 is also a means offilling the gaps and spaces left between the assembled parts to preventany remaining play due to the tolerances required for manufacturing allthe parts and secure all the parts of the assembly together in theiroperating positions. Sufficient mechanic strength is required to sustaincompression mainly due to the torque generated by the operating partsand transferred to the axial members 26 of the TFEM 10. The selectedresin 248 should also be a good vibration damper to protect the cores130, the coil 134 and their respective halves 32 and prevent anyundesirable contact between the operating parts of the TFEM 10. Thermalconductivity is another desirable role of the resin 248 that replacesair (empty volumes) in the phase module 32 to cool the internal parts ofthe TFEM 10 by transferring thermic energy to the environment of theTFEM 10. The resin 248 should also be tolerant to temperature variationsthat can reach between −40° C. and 180° C. with minimal changes in itsmechanical properties. The resin prevents conducting magnetic fluxwithin the internal parts of the phase module 32 that would preventproper flux transfer with the cores 130 around the coil 134. The resinshould also prevent creating Foucault current within the internal partsof the phase module 32 and therefore prevent additional energy loss.Finally, the resin 248 should be adapted to be machined to set the finaldimensions of the interior of the stator portion 14 to receive thereinthe rotor portion 18 with minimal airgap 126 therebetween. Epoxy resinis an example of a resin 248 suitable to be used in the present TFEM 10among other possible choices of resin 248 or other materials adapted tomeet the requirements listed above.

The second jig module 214 is provided with injection inlets 240, toinject resin or polymer in the mold, and injection outlets 244 to purge,or vacuum, air from the mold during the injection process. The sameprocess is used with each of the phase module 32 to get, in the contextof the present embodiment that is a three-phased alternator, threeinjected phase modules 32. Other configurations, other types of moldassembly and mold inlets/outlets can be used without departing from thescope of the exemplified invention.

Three injected phase modules 32 are assembled together as explainedabove and the result is shown in FIG. 34. The resin injected in thephase module 32 secures the coil 134, the cores 130 in the angularportions 146 in addition to secure the angular portions 146 and theirrespective halves 150 together. The resin thus injected transforms thephase module 34 assembly in a unitary and integral phase module 32. FIG.34 should be viewed in light of FIG. 14 and from it one can appreciatethat the poles 138 of the cores 130 are not shown in FIG. 34. This isbecause the resin injected in the phase module 32 covers the cores 130and a further step is required to carefully remove a layer of resininside the assembled core modules 32. The three (3) assembled phasemodules 32 are preferably bored, and optionally honed, once assembledtogether to remove excess resin and shortens the length of the core'slegs 142 to a desired diameter to ensure tight tolerances can beobtained for the diameter and the concentricity of the multiple coremodules 32 assembly in order to minimize the airgap 126 when the rotorportion 18 is assembled with the stator portion 14. A small airgapincreases the magnetic field strength between the stator portion 14 andthe rotor portion 18. One can appreciate that machining all the separatepart individually and assembling them thereafter is going to cause anaddition of the tolerances that is likely going to increase the finalairgap 126 to prevent possible (statistically possible) mechanicalinterferences. Alternatively, each phase module 32 can individually bebored and honed individually prior to be assembled with adjacent phasemodules 32. The final result, when stator boring is done, is illustratedin FIG. 14.

FIG. 35 generally illustrates a series of steps adapted to assemble tostator portion in accordance with an embodiment of the invention. FIG.36 illustrates illustrative steps for securing the parts of the statorportion together in accordance with at least one embodiment of theinvention.

The description and the drawings that are presented above are meant tobe illustrative of the present invention. They are not meant to belimiting of the scope of the present invention. Modifications to theembodiments described may be made without departing from the presentinvention, the scope of which is defined by the following claims:

What is claimed is:
 1. A housingless transverse flux electrical machine(TFEM) comprising: a stator including at least one phase modulecomprising a pair of opposed halve members respectively including aplurality of core-receiving spaces sized and designed to receive, locateand secure therebetween a plurality of cores; and a coil operativelydisposed in respect with the cores inside each phase modules, the pairof opposed halves being the exterior housing of the stator allowing theTFEM to be used without further housing.
 2. The housingless transverseflux electrical machine (TFEM) of claim 1, wherein the phase module isaxially binded with support portions compressing the at least one phasemodule.
 3. The housingless transverse flux electrical machine (TFEM) ofclaim 2, wherein the support portions are bound together with aplurality of securing members.
 4. The housingless transverse fluxelectrical machine (TFEM) of claim 3, wherein the plurality of securingmembers are disposed on the outside of the at least one phase module. 5.The housingless transverse flux electrical machine (TFEM) of claim 2,wherein the support portions support the at least one phase module andis adapted to operatively secure the TFEM to a support structure.
 6. Thehousingless transverse flux electrical machine (TFEM) of claim 2,wherein the support portions, when axially seen, are visually coveringthe entire at least one phase module.
 7. The housingless transverse fluxelectrical machine (TFEM) of claim 1, wherein at least some of thehalves members are visible when the TFEM is in operation.
 8. Thehousingless transverse flux electrical machine (TFEM) of claim 1,wherein halves comprise radial plans perpendicular to the rotationalaxis of the TFEM.
 9. The housingless transverse flux electrical machine(TFEM) of claim 1, wherein a distal radial surface of the phase moduleis waterproof.
 10. The housingless transverse flux electrical machine(TFEM) of claim 1, wherein a distal radial surface of the phase moduleis cylindrical and parallel with the rotational axis of the TFEM. 11.The housingless transverse flux electrical machine (TFEM) of claim 10,wherein the phase module further comprise resin therein for securing thecoil and the plurality of cores in the halves.
 12. A housingless statoradapted to be used in a rotatable transverse flux electrical machine(TFEM), the housingless stator comprising: at least one phase modulecomprising a pair of opposed halve members respectively including aplurality of core-receiving spaces sized and designed to receive, locateand secure therebetween a plurality of cores; and a coil operativelydisposed in respect with the cores inside each phase modules, the pairof opposed halves being the exterior housing of the stator allowing theTFEM to be used without further housing.
 13. The housingless stator ofclaim 12, wherein the phase module is axially bound with supportportions compressing the at least one phase module.
 14. The housinglessstator of claim 13, wherein the support portions are bound together witha plurality of securing members.
 15. The housingless stator of claim 14,wherein the plurality of securing members are disposed on the outside ofthe at least one phase module.
 16. The housingless stator of claim 14,wherein the support portions support the at least one phase module andis adapted to operatively secure the TFEM to a support structure. 17.The housingless stator of claim 14, wherein the support portions, whenaxially seen, are visually covering the entire at least one phasemodule.
 18. The housingless stator of claim 12, wherein at least some ofthe halve members are visible when the TFEM is in operation.
 19. Thehousingless stator of claim 12, wherein halves comprise radial plansperpendicular to the rotational axis of the TFEM.
 20. The housinglessstator of claim 12, wherein a distal radial surface of the phase moduleis cylindrical and parallel with the rotational axis of the TFEM.